Cell Structure Biology
Looking at cells Cells vary greatly in size and shape There are at least 200 types of cells There are 100 trillion cells in the human body most range from 5-20 mm Somatic Cells: Body Cells Sex Cells: Reproductive Cells
Cell Size http://learn.genetics.utah.edu/content/begin/cells/scale/
The Discovery of Cells Most cells are too small to see with the naked eye Microscope observations have led to the discovery of the basic characteristics of living things.
Cell History Antony van Leeuwenhoek Early 1600's Developed the first microscope First to see protists Named protists -Wee Beasties
Leeuwenhoek’s First Microscope
Cell History Robert Hooke 1665 Looking at cork Named cells
Robert Hooke’s Drawings
Cell History Matthias Schleiden 1838 All plants are made of cells
Cell History Theodor Schwann 1839 All animals are made of cells
Cell History Robert Brown 1840 Discovered cell nuclei in the epidermal cells of orchids Named the nucleus or center
Cell History Rudolph Virchow 1858 New cells come from old cells
Cell Theory 1. All living things are made of cells 2. Cells are the basic building block of life 3. New cells come from old cells Cell theory was developed over hundreds of years and many scientists
Prokaryotic and Eukaryotic Cells